The need to extend the features of Cloud computing to the edge of the network has fueled the development of new computing architectures, such as Fog computing. When put together, the combined and continuous use of fog and cloud computing, lays the foundation for a new and highly heterogeneous computing ecosystem, making the most out of both, cloud and fog. Incipient research efforts are devoted to propose a management architecture to properly manage such combination of resources, such as the reference architecture proposed by the OpenFog Consortium or the recent Fog-to-Cloud (F2C). In this paper, we pay attention to such a combined ecosystem and particularly evaluate the potential benefits of F2C in dynamic scenarios, considering computing resources mobility and different traffic patterns. By means of extensive simulations we specifically study the aspects of service response time, network bandwidth occupancy, power consumption and service disruption probability. The results indicate that a combined fog-to-cloud architecture brings significant performance benefits in comparison with the traditional standalone Cloud, e.g., over 50% reduction in terms of power consumption.

Future IoT services execution may benefit from combining resources at cloud and at the edge. To that end, new architectures should be proposed to handle IoT services in a coordinated way at either the edge of the network, the cloud, or both. Reacting to that need, the Fog-to-Cloud concept has been recently proposed. A key aspect in the F2C design refers to security, since F2C raises security issues besides those yet unsolved in fog and cloud. Thus, we envision the need for new security strategies to handle all components in the F2C architecture. In this paper we propose an SDN-based (mater/slave) security architecture leveraging a centralized controller on the cloud, and distributed controllers at the edge of the network. We argue that the proposed architecture brings more security and privacy to the cloud users by reducing the distance between them and, therefore, reducing the risks of the so called man-in-the-middle attacks. The proposed security architecture is analyzed in some critical infrastructure scenarios in order to illustrate their potential benefits.

Fog computing brings cloud computing capabilities closer to the end-device and users, while enabling location-dependent resource allocation, low latency services, and extending significantly the IoT services portfolio as well as market and business opportunities in the cloud sector. With the number of devices exponentially growing globally, new cloud and fog models are expected to emerge, paving the way for shared, collaborative, extensible mobile, volatile and dynamic compute, storage and network infrastructure. When put together, cloud and fog computing create a new stack of resources, which we refer to as Fog-to-Cloud (F2C), creating the need for a new, open and coordinated management ecosystem. The mF2C proposal sets the goal of designing an open, secure, decentralized, multi-stakeholder management framework, including novel programming models, privacy and security, data storage techniques, service creation, brokerage solutions, SLA policies, and resource orchestration methods. The proposed framework is expected to set the foundations for a novel distributed system architecture, developing a proof-of-concept system and platform, to be tested and validated in real-world use cases, as envisioned by the industrial partners in the consortium with significant interest in rapid innovation in the cloud computing sector.

The recent technological advances related to computing, storage, cloud, networking and the unstoppable deployment of end-user devices, are all coining the so-called Internet of Things (IoT). IoT embraces a wide set of heterogeneous services in highly impacting societal sectors, such as Healthcare, Smart Transportation or Media
delivery, all of them posing a diverse set of requirements, including real time response, low latency, or high capacity. In order to properly address such diverse set of requirements, the combined use of Cloud and Fog computing turns up as an emerging trend. Indeed, Fog provides low delay for services demanding real time response, constrained to support low capacity queries, whereas Cloud provides high capacity at the cost of a higher latency. It is with no doubt that a
new strategy is required to ease the combined operation of cloud and fog infrastructures in IoT scenarios, also referred to as Combined Fog-Cloud (CFC), in terms of service execution performance metrics. To that end, in this paper, we introduce and formulate the QoS-aware service allocation problem for CFC architectures as an integer optimization problem, whose solution minimizes the latency experienced by the services while guaranteeing the fulfillment of the
capacity requirements.

Amongst the few distinctive European alliances carrying the promise of making a lasting impact in software-defined networking (SDN) and the IT industry is the research and industrial communities pursuing developments in the Path Computation Element (PCE), an effort 'made-in-the-EU'. In regards to PCE design, deployment, and evolution, Europeans are amongst today's leaders in the process of transitioning PCE from software-defined concept to interoperable networking standards. This is particularly the case in the standardization bodies of IETF and ETSI, including the areas of advanced optical networks, sensor networks as well as frameworks for the Internet of Things (IoT).\nWe are still facing a number of open challenges in the SDN areas, yet to be addressed through PCE design. First, current Open Networking Foundation (ONF) specifications lack control systems and well-defined interfaces with external (non-ONF) functions, which represents a not-to-be-missed opportunity for the PCE-based architecture. Second, the new ETSI initiative on Network Functions Virtualization (NFV) is leveraging virtualization concepts, with the growing role of PCE concepts. Third, Application-based Network Operations (ABNO) – an architecture proposed, developed and led within the IETF by leading members of our consortium – uses a variety of PCE-based tools and techniques.\nPACE seizes this great opportunity of consolidation of the existing PCE developments, thereby facilitating a one-stop solution for all PCE-related issues, with an open-source software repository, workshops, standardization activities, plugin marketplace, etc. PACE will bring together a community of standardization and community leaders, developers, and academics. PACE will ensure that different aspects of PCE are not developed in isolation, while addressing interoperability issues, and thus avoiding any delays in innovation, and in sealing European leadership in the sector.

Context-aware applications are fast becoming popular as a means of enriching users’ experiences in various multimedia content access and delivery scenarios. Nevertheless, the definition, identification, and representation of contextual information are still open issues that need to be addressed. In this paper, we briefly present our work developed within the VISNET II Network of Excellence (NoE) project on context-based content adaptation in Virtual Collaboration Systems (VCSs). Based on the conducted research, we conclude that MPEG-21 Digital Item Adaptation (DIA) is the most complete standardization initiative to represent context for content adaptation. However, tools defined in MPEG-21 DIA Usage Environment Descriptors (UEDs) are not adequate for Virtual Collaboration application scenarios, and thus, we propose potential extensions to the available UEDs.